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I took some photos a few years ago when doing research in Oxford. I submitted them to a photo competition which unfortunately I didn't win. However, they are now being used in a new blog aimed at young non-sciencey types to raise awareness and enthusiasm for science. The following is a copy and paste from the blog, http://bbsrc.tumblr.com, the post from the 3 March 2014.

Lasers light the way to new drugs

Look beyond the pretty lights and lasers and you will see a Total Internal Reflection Fluorescence Array; a special type of model microscope that allows for multiple drug tests to be run simultaneously.

The test works by putting a drug and marker proteins inside an artificial cell, and then measures the effect the drug has on the speed that ions move into the cell.

This equipment, although only a concept device, could be key to new drug developments.

Recently, I've been playing with 2nd shutter sync. This simply means the camera flashes at the end of an exposure instead of at the beginning. This lends itself perfectly for capturing motion on longer exposures then effectively freezing the subject at its last position.

A few weeks ago I entered an ICAEW student photo competition:

Contest InstructionsUnleash your creativity. Is accountancy just something you do for a job or does it mean more than that? What images, objects, places or people does accountancy evoke?

I decided to use this technique to make it look like I was writing quickly while working on a set of accounts. Unfortunately I didn't win, I lost to a (admittedly well shot) picture of three meerkats titled Safety in Numbers. Regardless, I'm pleased with my entry:

While out of the country, relaxing in Spain, I continued my experimentation with 2nd shutter sync. This time instead of capturing the final position of a movement as above I tried something a little different...

Playing in Spain

I've seen loads of photos taken where people use a light and a long exposure to create patterns or words in the image. I've even done it myself:

Photo taken as part of the marketing for The Queen's College (Oxford) Commemoration Ball 2010

The problem with these photos is you don't see who is behind the pattern or the text. In Spain, I combined this interesting type of photo with the 2nd shutter sync to capture the people behind the photo, in the same exposure. Obviously this can be done with photoshop and I have compared the final result for the two methods below.

All of the following are single exposure images.

Due the limited creativity of those involved (myself included) there were no interesting pictures, only names and usernames to be seen, but at least everyone could introduce them in their own way! Apart from the Bez image (which has had the light colour altered) they have only had very basic adjustments made, such as brightness and colour balance etc

These look like they could have been made using composite imagery. As promised, I tried that too:

4 piece composite image

This is made up of 4 images. Due to the significantly shorter exposure times the body is more clearly visible in the four sections, "person", "Jake", "#" and "11". While there are benefits to creating the image in this way (such as easy retakes of particular sections), the finished product feels less authentic.

In my last post I showed some of the interesting effects that can be made with HDR. I tried to make it clear that the technique can also be used to create enhanced but realistic photos. As I explained, HDR is used to add additional light information to the photo which allows these extreme effects to be created. To demonstrate a more realistic processing I'm going to use the same starting image as last time:

Original

Software Edit

As can be seen in the original image the sky is overexposed while the shadows are very dark. While this can be edited in any decent photo software, the result will look similar to the right image. This edited image shows far more detail in the shadows and some more in the sky. This edit was only made possible due to the camera saving into a RAW format.

5 Image HDR

The final edit shows the same level of improvement over the original photo (in terms of detail) as the dramatic edits of the last post. The same type of processing is applied but less strongly allowing the photo to retain a more natural feel.

HDR stands for High Dynamic Range. HDR basically refers to an image having a range of brightnesses greater than the camera is capable of capturing, in a single photo. The way these are taken is with a series of exposures which with computer trickery are combined into a 32bit picture file. These cannot be displayed on normal computer screens/TVs so are 'photoshopped' back to a regular 16 or 8bit file. While this can give realistic results, it also allows for some wacky effects to be created.

I'm not going to go into the details on how to create these effects but will provide some links to tutorials at the bottom. I wanted to test the benefit of multiple exposure HDR over single exposure pseudo-HDR (the cheat method*). Additionally, I wanted to test how many exposures are needed for the best result. The three examples below show some of the effects HDR photography can lead to:

Single Vs Multiple Exposure HDR

There are times when either are appropriate but traditionally, the 'best' results will always come from a multiple exposure HDR. If there is movement in the scene you will get ghosting, which is the name given to the strange grey halos found around the moving objects (this can include plants/leaves moving in the wind). Software can reduce ghosting and in certain cases, remove it completely but a detailed tree scene on a windy day is going to have too much movement. *In these cases you can try single exposure HDR; this is only effective if you camera saves in RAW mode. Continue reading →